OC spray does not work on approximately 10% of people.
Based on my experience as an instructor and an end user, I would up that percentage, maybe double it.
It also has little effect on those under the influence of PCP
...or those drunk our of their minds, on a number of stimulants, etc.
Yeah, sometimes.
It worked on me, and it worked on the only combative suspect whom I squirted.
It doesn't "work" on me (it serves to piss me off an closes my eyes for a
very short period of time). It also doesn't work for schit on working dogs.
I don't carry the schit on my belt anymore and sure as hell wouldn't bet my safety on it in the woods (yes, I know bear spray and LEO OC are different).
George